429 SPH EROMID&. 
joint is obconical, and the flagellum multiarticulate. The 
last joint of the tail is centrally very convex, but the 
outer margin, both laterally and posteriorly, is flattened, 
and the terminal slit is considerably widened at its base ; 
the extremities of the sides of the slit sometimes closely 
approximating or touching each other; the lateral ap- 
pendages have the outer division rather smaller than the 
inner. The dactylos of the feet is armed on its inside 
with a strong tooth. Our figure c represents the head 
seen from the front, the oral appendages are therefore 
represented as foreshortened. 
In the young state, the sides of the terminal slit of the 
tail gape to a considerable width at their extremities. 
Montagu and Leach found this species in company 
with the preceding in great quantities, and Mr. W. 
Thompson took it at Lahineh, in Co. Clare, Ireland. 
